By contact information I mean main location, phone number and contact person or ceo.
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AliceSep 17 '12 at 13:02

It depends on the company. For example, the following quote is from the Terms of Use ( fisglobal.com/termsofuse ) of a site I work on: "The material, information, and content on this Web site are copyrighted property of FIS and may not be copied, distributed, republished, uploaded, posted, or transmitted without express written consent. Any reproduction, modification, or other use is expressly prohibited." ... If I were in your situation, I would contact each company directly to see what they're okay with.
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Will PeavySep 17 '12 at 17:30

It's better to contact them and ask them first or as suggested read their terms of services. but if you can't, I recommend you to do some protections against spam crawlers or email address harvester robots and then put a disclaimer note somewhere near this listing.

As long as you display public information there is no legal concern. Any business directory out there is providing the same information and you don't have to contact or read privacy notices - again as long as you don't display sensitive information.

You can even publish financial records of the companies if you have access to them as again, this is also public information.

Since you said it's good for your users I would suggest setting all the new pages on no index, do follow so Google won't index this duplicate content so you can run into Google related issues. (At the end of the day is the exact same content that is probably available on several other business directories.)